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The Arrangement and Size of Cellulose Microfibril Aggregates in the Cell Walls of Sclerenchyma Fibers and Parenchyma Tissue in Bamboo

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Journal of Renewable materials 2021年第12期9卷 2291-2301页

作者： Wenting Ren Fei Guo Minghui Liu Haocheng Xu Hankun Wang Yan Yu Institute of New Bamboo and Rattan Based Biomaterials International Center for Bamboo and RattanBeijing100102China College of Material Engineering Fujian Agriculture and Forestry UniversityFuzhou350108China NFGA and Beijing Co-Built Key Laboratory of Bamboo and Rattan Science&Technology National Forestry and Grassland AdministrationBeijing100102China

Understanding the assembly and spatial arrangement of bamboo cell wall components is crucial for its optimal *** cell walls consist of aggregates of cellulose microfibrils and *** the present study,the size and arrangement of cellulose microfibril aggregates in the cell walls of sclerenchyma fibers and parenchyma cells in moso bamboo were investigated with NMR and *** NMR measurement showed that the characteristic sizes of the microfibril aggregates of fibers and parenchyma cells were approximately 25.8 nm and 18.8 nm,***,high-resolution SEM showed the size of microfibril aggregates varied little across the cell wall of sclerenchyma ***,there were significant size differences between the broad and narrow lamellae both in fiber and parenchyma cells,which is thought to be closely related to the orientation of microfibrils in these *** microfibril aggregates in the fibers mainly appear in a random arrangement,although occasionally in a radial or tangential arrangement in individual *** cells have a relatively thinner cell wall layers,in which microfibril aggregates appear in a concentric lamellar arrangement.

关键词： Bamboo fiber parenchyma cell microfibril aggregate size arrangement

Anti-Ultraviolet, Co2 Permeability and Photothermal Properties of Porous Pva-G-Alkali Lignin-based Coumarin Composite Membranes

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SSRN 2024年

作者： Shi, Ying Mu, Haohao Wang, Qian Wang, Juan Liu, Yuan Yuan Ren, Shixue Song, Yongming Ma, Yanli Li, Shujun Key Laboratory of Bio-based Material Science & Technology Northeast Forestry University Ministry of Education Heilongjiang Harbin150040 China Engineering Research Center of Advanced Wooden Materials Ministry of Education Heilongjiang Harbin150040 China

Polyvinyl alcohol (PVA) is widely used in food packaging, drug release materials, and crop growth applications but suffers from accelerated aging due to sunlight exposure. Lignin can be used as a filler in polymer membranes to prevent degradation and to block the ultraviolet light that is harmful to crops and plants. However, traditional blending methods result in composite membranes with inferior mechanical properties compared to pure PVA ***, PVA-g-LGC is synthesized with PVA and alkali lignin-grafted 3-acryloyl-7-diethylamino coumarin (LGC). LGC serves as an UV-responsive pore-forming agent, facilitating the radical copolymerization of PVA with LGC. PVA-g-LGC exhibits an ultraviolet transmission value approaching zero within the 200 to 400 nm range. Subsequently, it was discovered that the transmittance of visible light for the PVA-g-LGC membrane surpasses that of a PVA/LGC blending membrane by a significant margin of 155.2%. Furthermore, the CO2 permeable ability of the PVA-g-LGC membrane is astonishingly enhanced by a remarkable factor of 66.44 compared to the PVA membrane. Notably, after 9 min illumination under 1 sunlight, the temperature of the PVA-g-LGC membrane surface escalates to 34.6 °C, surpassing the temperature of the PVA/LGC blending membrane by 1.8 °*** work presents a facile one-step strategy to fabricate a porous PVA-g-LGC composite membrane with UV protection, enhanced CO2 permeability, and photothermal insulation properties. Derived from alkali lignin, this environmentally friendly coating can prevent UV radiation damage to people, animals,and plants and protect indoor and outdoor decorations from discoloration,making it a promising material for sustainable applications. © 2024, The Authors. All rights reserved.

关键词： Carbon dioxide

A Magnetic Wood with Degradable/Flame-Retardant Properties Obtained by Esterification Modification with Citric Acid

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SSRN 2023年

作者： Sun, Xiaoxiao Chen, Lei Zheng, Dingyuan Chen, Yang Yang, Minghui Yao, Wenrui Zhang, Yanhua Key Laboratory of Bio-based Material Science & Technology Northeast Forestry University Ministry of Education Harbin150040 China Hangzhou Hsinchu Cultural Creativity Co. LTD Hanzhou311200 China

Renewable energy has the advantages of environmental protection, sustainability and energy security, and therefore has become the current hotspot for promotion and development worldwide. As a renewable building material, wood offers great possibilities for sustainable urbanization. Here, we explored a new biodegradable wood (3%PFeW) of magnetic and flame-retardant by chemical methods, made of porous wood containing nano-Fe3O4 impregnated with citric acid, 1,8-octanediol and the copolymer flame retardant CEPPA. It has excellent magnetic properties, and has a magnetic saturation strength of up to 1.50 emu/g at 1.38% iron content. It is worth noting that the esterification of the citric acid carboxyl group with the cellulose hydroxyl which makes the 3%PFeW outstanding chemical stability marked by outstanding resistance to moisture absorption. Simultaneously, the existence of CEPPA contributes to the effective flame retardancy of the 3%PFeW. It can be self-extinguished after 10 s of ignition. Given biodegradation, simple operation, good durability, excellent magnetic properties and effective flame retardancy, the wood materials with magnetic and flame-retardant demonstrated here is an attractive induction magnetic and flame retardancy material for application in building and furniture. © 2023, The Authors. All rights reserved.

关键词： Chemical stability

Electrospun PVA Nanofibrous Membranes Reinforced with Silver Nanoparticles Impregnated Cellulosic Fibers:Morphology and Antibacterial Property

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Chemical Research in Chinese Universities 2021年第3期37卷 505-511页

作者： YAN Jie WANG Dong BAI Tian CHENG Wanli HAN Guangping NI Xiaohui SHI Q.Sheldon Key Laboratory of Bio-based Material Science&Technology Ministry of EducationNortheast Forestry UniversityHarbin150040P.R.China School of Art and Design Taizhou UniversityTaizhou318000P.R.China Mechanical Engineering Department University of North TexasUNT Discovery Park3940 North Elm St.Suite F101PDentonTexas76207-7102USA

To enhance the mechanical and antibacterial properties of silver nanoparticle impregnated cellulosic fibers,carboxy-cellulose nanocrystals(CCNs)were grafted with chitooligosaccharide(COS),which was used as a stabilizer for silver nanoparticles(AgNPs).Nanofibrous membranes reinforced with silver nanoparticle impregnated cellulosic fibers(CCN-COS-AgNP)were prepared via electrospinning using polyvinyl alcohol(PVA)as a *** effects of CCN-COS-AgNP contents on the morphology,surface composition,mechanical properties,and antibacterial performances of the prepared CCN-COS-AgNP/PVA membranes were *** addition of CCN-COS-AgNP certainly improved the mechanical properties and antibacterial performances of the PVA *** tensile strength was significantly increased from 4.40 MPa to 8.60 MPa when 8%CCN-COS-AgNP(mass ratio)was *** 10%(mass ratio)CCN-COS-AgNP was added,the nanofibers showed an excellent antibacterial activity for ***(Staphylococcus aureus)and ***(Escherichia coli),with the maximum inhibition zones of 2.30 and 1.60 cm,***,the 2%(mass ratio)CCN-COS-AgNP/PVA fibrous membrane showed 126%cell viability for mg63 human *** electrospun PVA membrane has great potential application in biomedical field.

关键词： Electrospun membrane Carboxy-cellulose Silver nanoparticle Antibacterial performance Polyvinyl alcohol

Facile Construction of a Micro-Nano Structure of Green Polyvinyl Alcohol-based Composite Aerogel with Superior Mechanical Properties, Thermal Insulation And Fire Safety

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SSRN 2025年

作者： Gao, Suliang Wang, Ruiping Zhang, Hui Xu, Miaojun Tao, Bin Xue, Han Liu, Lubin Li, Sheng Li, Bin Key Laboratory of Bio-based Material Science and Technology of Ministry of Education Northeast Forestry University Hexing Road 26 Harbin150040 China Heilongjiang Key Laboratory of Molecular Design and Preparation of Flame Retarded Materials College of Chemistry Chemical Engineering and Resource Utilization Northeast Forestry University Harbin150040 China

In light of the "dual-carbon" targets, traditional thermal insulators have failed to meet the increasingly stringent demands for green sustainability and fire safety. In this work, a green polyvinyl alcohol (PVA)-based composite aerogel was successfully prepared using biomass-derive PVA and nano-silica sol as raw materials. The resultant aerogel presented a distinctive micro-nano composite hierarchical three-dimensional (3D) network structures, and diameter of the micro-scaled big pores ranged from 6.0 μm to 48.0 μm. Additionally, a large number of nano-scaled pores with an average diameter of 22.79 nm existed in the micro-scaled big pores, and the total pore volume of 0.66 cm3·g-1. Induced the unique structure of the aerogel, it exhibited a low bulk density of 0.081 g·cm-3and a high porosity of 94.97%, respectively, while its thermal conductivity was only 37.6 mW·m-1·K-1. Besides, compressive strength and specific modulus of the aerogel significantly increased to 3.98 MPa and 27.41 MPa·cm3·g-1, respectively. The composite aerogel achieved UL-94 V-0 rating during vertical burning tests with a limit oxygen index of 26.5%, and the release of heat, smoke and toxic gases were obviously lower than that of PVOH aerogel. This work provided an alternative approach for constructing the aerogels with high performance as well as superior fire safety, thermal insulation and mechanical performance. © 2025, The Authors. All rights reserved.

关键词： Compressive strength

Constructing Oxygen Vacancy-Regulated Cu/Fe2o3 Nanorod Array Electrodes for Boosting the Electrocatalytic Reduction of Nitrate

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SSRN 2024年

作者： Yang, Ziyi Li, Yudong Liu, Dan Song, Maosen Gao, Yang Yang, Bin He, Yanzhen Han, Enshan Yang, Xiaohui School of Chemical Engineering Hebei University of Technology Tianjin300400 China Key Laboratory of Bio-based Material Science & Technology Northeast Forestry University Ministry of Education Heilongjiang Harbin150040 China Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Chongqing400714 China

The adsorption of nitrate is the key to enhancing the electrocatalytic nitrate reduction reaction (NitRR). Constructing oxygen vacancies (OVs) has been an effective strategy that can modulate the local electronic structure and enhance the adsorption of nitrate. However, the existing methods for effectively regulating the concentration of oxygen vacancies are still limited. Herein, based on a detailed understanding of the NitRR mechanism, a typical hydrolysis-coupling redox (HCR) reaction has been designed to prepare unique 3D Cu/Fe2O3 core-shell nanorod array cathodes with controllable oxygen vacancy concentration. The optimal Cu/Fe2O3-13 achieves a high nitrate conversion of 99.10 % and ammonia selectivity of 98.30 % in a 0.2 M Na2SO4 solution with 100 ppm -N at -1.4 V vs. SCE. Furthermore, the Cu/Fe2O3-13 exhibits exceptional stability throughout a 30-hour electrocatalytic process. The outstanding electrochemical performance is attributed to the enhancement mechanism of OVs and a unique nanorod array structure with a high density of surface-exposed OVs and high-throughput transport pathways for ions-aspects. © 2024, The Authors. All rights reserved.

关键词： Electrocatalysis

Reprogramming the metabolism of Synechocystis PCC 6803 by regulating the plastoquinone biosynthesis

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Synthetic and Systems biotechnology 2021年第4期6卷 351-359页

作者： Jianhua Fan Dongqing Zhou Cheng Chen Ju Wu Hui Wu State Key Laboratory of Bioreactor Engineering East China University of Science and TechnologyShanghai200237PR China Department of Applied Biology East China University of Science and TechnologyShanghai200237PR China Shanghai Collaborative Innovation Center for Biomanufacturing Technology 130 Meilong RoadShanghai200237China Key Laboratory of Bio-based Material Engineering of China National Light Industry Council 130 Meilong RoadShanghai200237China

Cyanobacteria can utilize CO2 or even N2 to produce a variety of high value-added products ***(PQ)is an important electron carrier in both of the photosynthetic and respiratory electron transport *** the content of PQ,as well as their redox state,have an important effect on physiology and metabolism,there are relatively few studies on the synthesis of PQ and its related metabolic regulation mechanism in photosynthetic *** this study,the strategies of overexpression of Geranyl diphosphate:4-hydroxybenzoate geranyltransferase(lepgt)and addition of 4-hydroxybenzoate(4-HB)as the quinone ring precursor were adopted to regulate the biosynthesis of PQ in Synechocystis PCC *** with the analysis the photosystem activity,respiration rate and metabolic components,we found the changes of intracellular PQ reprogrammed the metabolism of Synechocystis PCC *** results showed that the overexpression of lepgt reduced PQ content dramatically,by 22.18%.Interestingly,both of the photosynthesis and respiration rate were *** addition,the intracellular lipid and protein contents were significantly ***,the addition of low concentrations of 4-HB enhanced the biosynthesis of PQ,and the intracellular PQ contents were increased by 14.76%-70.86%in different *** of 4-HB can regulate the photosystem efficiency and respiration and reprogram the metabolism of Synechocystis PCC 6803 *** a word,regulating the PQ biosynthesis provided a novel idea for promoting the reprogramming the physiology and metabolism of Synechocystis.

关键词： Cyanobacteria Plastoquinone LePGT 4-HB Metabolic rewiring

Citric Acid/Chitosan Adhesive with Viscosity-Controlled for Wood Bonding Through Supramolecular Self-Assembly

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SSRN 2023年

作者： Cai, Lijian Chen, Yutong Lu, Zetan Wei, Ming Zhao, Xin Xie, Yanjun Li, Jian Xiao, Shaoliang Key Laboratory of Bio-based Material Science & Technology Ministry of Education Northeast Forestry University Harbin China Engineering Research Center of Advanced Wooden Materials Ministry of Education Northeast Forestry University Harbin China

Developing bio-based sustainable wood adhesives is significant as a substitute for petroleum-derived adhesives. However, the existing bio-based adhesives have disadvantages of complex fabrication, uncontrollable viscosity, and poor water resistance. Herein, we developed a citric acid/chitosan adhesive with viscosity-controlled and water-resistant features by one-step dissolution at room temperature based on the supramolecular self-assembly strategy. Different wood products (plywood, laminated veneer lumber and particleboard) with superior performance were prepared by applying that adhesive on veneer and wood particles (fine particles and rough particles). The adhesion mechanism was mechanical interlocks and cross-linking of citric acid/chitosan in adhesives with those in the cell wall. This work provides high promise for alternatives to traditional unsustainable wood adhesives (urea-formaldehyde, melamine-urea-formaldehyde and phenolic resins) for fabricating different wood products. © 2023, The Authors. All rights reserved.

关键词： Adhesives

Construction of Moiré-Like Tio2/Polypyrrole Electrodes for High Performance Photo-Assisted Supercapacitors

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SSRN 2024年

作者： Cai, Hanwen Li, Yudong Liu, Dan Yang, Xiaohui Zhou, Desheng Han, Enshan Li, Xinhao Li, Qingyue He, Yanzhen School of Chemical Engineering and Technology Hebei University of Technology Tianjin300130 China Hebei Key Laboratory of Functional Polymers Tianjin300130 China Key Laboratory of Bio-based Material Science & Technology Northeast Forestry University Harbin150040 China Chongqing Institute of Green and Intelligent Technology Chinese Academy of Sciences Chongqing400714 China School of Energy Science and Engineering Harbin Institute of Technology Harbin150001 China

There is currently a need for research into using external energy to increase the performance of the supercapacitor in energy storage systems because of their poor energy density. This paper reports the effective creation of photo-assisted supercapacitors with moiré-like morphology using polypyrrole (PPy) and titanium dioxide nano powder to replicate the surface of inexpensive and widely available CD discs. The composite material combines the moiré-like superstructure's strong light trapping property with titanium dioxide's high photo-sensitivity, achieving the aims of boosting light absorption, extending the optical route, and improving capacitor performance under light. By combining morphology construction and external energy interventions to improve capacitor performance, the specific capacitance under light is 509.0 F g-1 at 1 A g-1, 13.1% higher than the same material without moiré-like morphology (449.9 F g-1). When assemble into a sandwich-structured symmetric supercapacitor, it has an area specific capacitance of 99.42 mF cm-2 and an energy density of 7.28 Wh kg-1 at a power density of 217.4 W kg-1, outperforming typical photo-assisted supercapacitors. The current work suggests a practical and straightforward method for increasing the light absorption efficiency and performance of photo-assisted supercapacitors. © 2024, The Authors. All rights reserved.

关键词： Morphology